The Wittig rearrangement of alpha-lithioethers will be studied as a synthetic method for carbocyclic rings. An attempt will be made to develop a general synthesis of alpha-lithioamines. Alpha-Lithiocyclopropyl ethers will be used in the preparation of four- and six-membered rings which are fused to other rings. The stereospecific construction of fused bicyclic systems by the use of Diels-Alder reaction of phenylthio-substituted butadienes with dienophiles will also be attempted.